/*
 * Copyright (c) 2013. wyouflf (wyouflf@gmail.com)
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package com.dongfang.utils.core;

import java.util.concurrent.ConcurrentHashMap;

/**
 * Author: wyouflf Date: 13-8-1 Time: 上午11:25
 */
public class KeyExpiryMap<K, V> extends ConcurrentHashMap<K, Long> {
	private static final long serialVersionUID = 1L;

	private static final int DEFAULT_CONCURRENCY_LEVEL = 16;

	public KeyExpiryMap(int initialCapacity, float loadFactor, int concurrencyLevel) {
		super(initialCapacity, loadFactor, concurrencyLevel);
	}

	public KeyExpiryMap(int initialCapacity, float loadFactor) {
		super(initialCapacity, loadFactor, DEFAULT_CONCURRENCY_LEVEL);
	}

	public KeyExpiryMap(int initialCapacity) {
		super(initialCapacity);
	}

	public KeyExpiryMap() {
		super();
	}

	@Override
	public synchronized Long get(Object key) {
		if (this.containsKey(key)) {
			return super.get(key);
		}
		else {
			return null;
		}
	}

	@Override
	public synchronized Long put(K key, Long expiryTimestamp) {
		if (this.containsKey(key)) {
			this.remove(key);
		}
		return super.put(key, expiryTimestamp);
	}

	@Override
	public synchronized boolean containsKey(Object key) {
		boolean result = false;
		if (super.containsKey(key)) {
			if (System.currentTimeMillis() < super.get(key)) {
				result = true;
			}
			else {
				this.remove(key);
			}
		}
		return result;
	}

	@Override
	public synchronized Long remove(Object key) {
		return super.remove(key);
	}

	@Override
	public synchronized void clear() {
		super.clear();
	}
}
